不同管理模式下农田水氮利用效率及其环境效应  

Analysis of Water and Nitrogen Use Efficiencies and Their Environmental Impact Under Different Water and Nitrogen Management Practices

作　　者：王欢元[1] 胡克林[1] 李保国[1] 金梁[1] 

机构地区：[1]中国农业大学资源与环境学院/教育部植物-土壤相互作用重点实验室,北京100193

出　　处：《中国农业科学》2011年第13期2701-2710,共10页Scientia Agricultura Sinica

基　　金：国家重点基础研究发展规划项目(2009CB118607);国家科技支撑计划项目(2008BADA7B05);国家公益性行业(农业)科技专项(200803036);中德合作项目(GRK1070/1);中国农业大学研究生科研创新专项(KYCX2010074)

摘　　要：【目的】定量化不同水氮管理模式下的农田水氮利用效率和环境效应,为制定优化的水肥管理措施提供理论指导。【方法】在华北平原北部的冬小麦-夏玉米轮作区,设置了农民习惯和基于土壤水分养分实时监测的优化管理两种水氮管理模式。首先,应用田间系统的观测数据(2004年10月至2006年9月)对水氮管理模型进行了校验,然后应用校验后的模型计算得到了两种水氮管理模式下的作物产量、农田水分渗漏、氮素淋失、气体损失和水氮利用效率等。【结果】2年内农民习惯和优化管理下的灌水量差别不大,而优化管理的施肥量(540 kg N.hm-2)仅为农民习惯施肥量(1 100 kg N.hm-2)的一半。农民习惯和优化管理模式下的作物年平均产量分别为11 579和11 748 kg.hm-2;两者的水分利用效率分别为1.65和1.72 kg.m-3;氮素利用效率分别为15和24 kg.kg-1 N。氮素淋失和氨挥发是氮素损失的主要途径,农民习惯和优化管理下的氮素淋失分别为407和68 kg N.hm-2;氨挥发分别达到了282和104 kg N.hm-2。【结论】优化管理下的作物产量和水氮利用效率都高于农民习惯管理的,并且氮素损失明显低于农民习惯管理。因此,为了保证该地区的农业可持续发展,必须改进当前农民习惯的水氮管理措施。[Objective] The objective of this study was to quantify water and nitrogen use efficiencies （WUE and NUE） and their environmental impact under different water and nitrogen management practices, and to provide some suggestions on making optimal management practice. [Method] Two kinds of water and nitrogen management practices, farmers＇ practice （FP） and reduced input （RI） practice based on real-time measure of soil water content and soil mineral N concentration, were both conducted under winter-wheat and summer-maize rotation system from Oct. 2004 to Sep. 2006 in the North China Plain （NCP）. After a Water and Nitrogen Management Model （WNMM） was calibrated and validated, the yields, amounts of drainage, N leaching, WUE and NUE for both treatments were all calculated. [ Result] The results showed that the difference of the irrigation amounts between the two treatments was small, while the difference of fertilizer application rate was significant, the amounts for RI （540 kg N·hm-2） was only half of that of FP （1 100 kg N·hm-2）. The annual average yields under FP and RI practices were 11 579 and ll 748 kg.hm2, respectively. The WUE for FP and RI were 1.65 and 1.72 kg·m3, respectively. Their NUE were 15 and 24 kg·kg-1 N, respectively. N leaching and NH3 volatilization were the main pathway of nitrogen loss. Amounts of N leaching were 407 and 104 kg N·hm-2 for FP and RI, respectively, and NH3 volatilization was 282 and 104 kg N.hm2 for FP and RI, respectively. [Conclusion] The yield, WUE and NUE under RI were all higher than those under FP, and total N loss under RI was significantly lower than that under FE Therefore, water and nitrogen management by farmers＇ practice should be improved to develop sustainable agriculture in the NCP.

关 键 词：华北平原 水氮管理模型 水分渗漏 氮素淋失 水氮利用效率 

分 类 号：S147[农业科学—肥料学] S274[农业科学—农业基础科学]